“Any time a state considers legalizing medical marijuana, there are concerns from the public about an increase in drug use among teens,” said principal investigator Choo, an attending physician in the department of emergency medicine at Rhode Island Hospital. “In this study, we examined 20 years worth of data, comparing trends in self-reported adolescent marijuana use between states with medical marijuana laws and neighboring states without the laws, and found no increase in marijuana use that could be attributed to the law.”

Choo, Researchers on Findings

Choo and her coauthors explain that the state-level legalization of medical marijuana has raised concerns about increased accessibility and appeal of the drug to youth, who are most vulnerable to public messages about drug use and to the adverse consequences of marijuana. Their study was performed to assess the impact of medical marijuana legalization in Rhode Island in 2006. The researchers compared trends in adolescent marijuana use between Rhode Island and Massachusetts using a self-report called the Youth Risk Behavioral Surveillance System. In their study, they included surveys completed between 1997 and 2009.

Based on their analysis of 32,570 students, they found that while marijuana use was common throughout the study period, there were no statistically significant differences in marijuana use between states in any year.

Choo says, "Our study did not find increases in adolescent marijuana use related to Rhode Island's 2006 legalization of medical marijuana; however, additional research may follow future trends as medical marijuana in Rhode Island and other states becomes more widely used."

The study was funded by a grant from the Rhode Island Foundation. Choo's principal affiliation is Rhode Island Hospital, a member hospital of the Lifespan health system in Rhode Island, and direct financial and infrastructure support for this project was received through the Lifespan Office of Research Administration. Choo also holds an academic appointment, assistant professor of emergency medicine, at The Warren Alpert Medical School of Brown University.